Yeah, you’ve got me thinking now. Since TR doesn’t have a setting for crank length, I better make sure it is set properly in the app. I forgot about that. I’m so used to using the computer, but I don’t use it with TR either … thanks for the wake-up for me.
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I may be wrong, but crank length is usually stored in the pedals, and will remain at that setting until it’s changed by another app.
Not sure if the Garmin interaction and bike setup will impact that?
There is a deafult value that you can set in the pedal but that will be overridden by the computer if it supports the feature. This makes it much easier to change the crank length whan you swap between bikes. On a garmin this is stored on a bike by bike basis rather than as a sensor setting.
Mike
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No problem. The app default is 172.5 so if that’s your length then it’s fine. Otherwise I heard it’s something like 3% variance for each increment so changing it from 172.5 to 175 would lower the power 3%, changing from 172.5 to 170 would raise it 3%. Could be wrong on the figures, probably am, but I wanna know. Apparently it’s a way people cheat in zwift races so I’m sure it’s not an insignificant amount
I’m not sure that this is the case on all edge units as they moved away from bike profiles with specific sensor pools.
On the garmin edge 1000 the crank length is located in settings>sensors>“Favero sensor name”>sensor details
It overrides whatever is currently stored on the pedals - most likely when you calibrate.
What I don’t know, and would like to know, is if the “new” value sent to the pedals from the garmin becomes the new default on the pedals for use when the crank length cannot be set on the recording device/software. I.e. if my garmin is set to 165 and my favero app to 172.5, and i linked to my head unit last, what is the crank length set to when I then use TR?
It would be good if TR could display what the crank is set to even if it doesn’t let you change it.
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Power = torque x cadence
Torque = Force x distance
So,
Power = force x distance x cadence
Assuming that the measured force and cadence are the same – power reported increases linearly with distance (crank length).
A 175 crank is around 1.5% longer than a 172.5 so if you set your crank length to 175, but you had a 172.5 crank, the power would report 1.5% higher than it should.
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Thanks for that. So effectively if someone had 172.5 cranks and changed their value to 155 they would get an 11-12% bump in power?
Interesting. I have a 510 and it’s stored as part of the bike profile on that device.
Other way round I think 
they would have a decrease in reported power.
Probably easiest just not to cheat to be safe 
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Oh I would never, just wondered how it worked because a friend of mine always beats one guy IRL races but always gets smoked on Zwift by the same guy.
The Assioma app warns explicitly that the value will be overridden by the bike computer, so I suspect that the bike computer is the equivalent to another app.
It doesn’t mention Garmin specifically, only that the bike computer will override.
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Yeah, after writing earlier I checked out the cranks on the bike I use on the trainer … 172.5 mm. I’m good, like you say. No problem.
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So how many people have given up on the XPEDO cleat and surrendered to buying covers for walking?
I use mine on power match, so they match up with outside work levels just fine. I’m going on two years and very happy.
Anyone tried these with Assioma?
That’s a rubbish place for that setting if you swap between bikes and crank lengths. Come to think of it my Garmin 935 does the same so I guess the current generation of garmin devices all do it this way.
Hi , i have noticed a difference when using my polar M460 and the road trainer along with my trainer and the pedals and with all using bluetooth you can not have more than 2 recording with bluetooth, so indoor i use trainer road and on the road my M460 and it seems ok as i can base the values on my h/r
Theres no more bike profile in Garmin Edge 520 or 530.
Everytime I change my pedals to/from my road/tt bike I have to change it. Its a PITA.
Does anyone knows a way to make this process easier?
I don’t need to change my crank lengths, but if I did, I reckon it’d take me around 10 seconds. That’d be a Right, Royal PITA - where am I going find 10 extra seconds before every ride?
I mean seriously, its probably going to take you 5 mins to swap the pedals between bikes anyway, so a few more seconds to set the correct crank length cannot hurt that much?
Talk about #firstworldproblems eh?
How many times a week do you need to swap the pedals? If time is so valuable, I’d suggest either:
A) getting the same crank length on both your bikes, or another set of Assioma. Then you can save the 10secs and the 5mins every time.
B) Dumb down your Garmin mofel to an older head unit that has bike profiles.
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